Re-use Of Wastewater Can Replenish Supplies

In El Paso, Texas, recycled wastewater is used to replenish scarce water supplies.

Since 1957, farmers in Vandalia, Mo., have used it to irrigate their corn crops.

This year, Orlando will begin a program to irrigate commercial orange groves with wastewater.

About 2,300 St. Petersburg residents are on a waiting list to hook their lawn sprinklers to a pipeline from the city`s sewage treatment plant.

In Orange County, Calif., highly treated wastewater is injected into the aquifer zone, forming a protective barrier between inland drinking water supplies and intruding saltwater from the Pacific Ocean.

As water becomes more precious, government officials across the nation are awakening to the value of treated wastewater.

From watering the lawn to replenishing drinking water suppiles, billions of gallons of this recycled water is now being put to use, not to waste.

Although it has gotten a late start, Palm Beach County is expected to be a more active participant in what could be called ``the reclaimed water generation`` in the late 1980s and early 1990s.

By doing so, the county each year would stop wasting an estimated 36.5 billion gallons of reclaimed water that is perfectly good for irrigation and industrial uses, regional water managers said.

Each gallon that is recycled will be one less drawn from the natural groundwater supplies, helping to ease the fast-growing demand for the freshwater reserves that supply the county`s drinking water.

Today, virtually all of the county`s treated wastewater is either flushed into the ocean or injected into holding wells thousands of feet underground, where it is forever lost as a water source for the county.

Since a severe drought earlier this decade, regional water managers have been aggressively urging South Florida`s cities and counties to find uses for reclaimed water.

Their philosophy: ``Waste not, want not.``

Their intent: To stretch the underground freshwater supplies for human necessities -- drinking, bathing and cooking -- instead of luxuries like golf courses and landscaping.

Treated wastewater is perfect for those uses, and perfectly safe, other communities have found.

The treated product is a far cry from the sewage that enters the system. Solids are removed, and the remaining water is filtered and treated with bacterial agents and chemicals. Afterward, it is comparable in quality to water pumped out of the ground, except for a high mineral content.

Recycling water involves no additional costs beyond those of normal treatment expense. Distribution is expensive, though, because a new network of water lines is needed. The first 80 miles of St. Petersburg`s wastewater pipeline cost $24 million.

The South Florida Water Management District already is pressuring local governments to use the resource for irrigation of golf courses and parks. The emphasis is renewed during water shortages such as last spring`s.

In addition, Stanley Hole, chairman of the water district`s governing board, said he expects the district may begin requiring water reclamation for new developments in the not-too-distant future.

``I suspect we`re going to require it on private properties. There are only so many shoulders on roads, parks, median strips (to irrigate). Once those are used up, I think we`ll start looking for private users when it is practical,`` he predicted.

Yet many neighborhoods probably will never get a chance to use reclaimed water because of the expense of installing new lines under existing roads, and because it simply may not be available, according to Stanley Winn, the water district`s re-use expert.

Winn predicted that the future demand for reclaimed water in Palm Beach County may actually exceed the supply.

Moreover, added Hole, the county is unlikely to ever need reclaimed water to directly supplement its drinking water supplies or recharge its wellfields, as is being done in El Paso and other growing cities in relatively arid regions.

In June, El Paso began injecting 10 million gallons of highly treated wastewater a day into the aquifer from which the city draws two-thirds of its drinking water.

The reclaimed water slowly seeps through a half-mile of cleansing sands before mixing with natural waters around the wellfields.

Compared with El Paso and sections of California, where water reclamation is widely accepted, Palm Beach County is water rich.

Yet like its arid western counterparts, Palm Beach County has faced water shortages. And, expecting future shortages, the water management district this year has been refining its water-use regulations.

Periods of below-average rainfall have created stress on groundwater reserves at a time when the county needs more and more water to satisfy the incessant demands of a fast-growing population.

About half of all water supplied by public and private utilities goes for non-necessities such as lawn watering, according to water district officials.